Two coast guard officers were found guilty and one cleared on Tuesday of torturing Moroccan migrants on Chios in 2007.
The navy tribunal handed the two men suspended jail sentences of three and six years.
One of their two victims appeared in court and said he was subjected to waterboarding and fake executions.
“We applaud this decision and we hope that it will act as a deterrent against criminal behavior toward refugees and immigrants of which members of the coast guard have been accused in the past,” said the Group of Lawyers for the Rights of Refugees and Migrants.
The abuse of the migrants was first brought to light by the German-based nongovernmental organization Pro Asyl.